* {
    margin: 0;
    padding: 0;
}

.game {
    width: 800px;
    height: 600px;
    margin: 5px auto;
    border: 2px solid black;
    overflow: hidden;
    position: relative;
}

.game .sky {
    background-image: url(./img/sky.png);
    width: 200%;
    height: 100%;
    position: absolute;
    left: 0;
    top: 0;
}

.game .land {
    background-image: url(./img/land.png);
    width: 200%;
    height: 112px;
    position: absolute;
    left: 0;
    bottom: 0;
}

.game .bird {
    width: 33px;
    height: 26px;
    position: absolute;
    top: 150px;
    left: 150px;
    background-image: url(./img/bird.png);
}

.game .bird.bird1 {
    background-position: -9px -9px;
}

.game .bird.bird2 {
    background-position: -61px -9px;
}

.game .bird.bird3 {
    background-position: -114px -9px;
}

.game .pipe {
    width: 52px;
    height: 100px;
    position: absolute;
    /* right: 100px; */
}

.game .pipe.up {
    background-image: url(./img/pipeDown.png);
    top: 0;
    background-position: bottom;
}

.game .pipe.down {
    background-image: url(./img/pipeUp.png);
    bottom: 112px;
}

.game .over {
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    position: absolute;
    top: 0;
    left: 0;
    color: #ffffff;
    font-size: 50px;
    font-weight: 400;
    text-align: center;
    line-height: 600px;
    display: none;
    z-index: 10;
}

.game .jifeng {
    position: absolute;
    color: black;
    top: 0;
    left: 0;
    z-index: 9;
    padding: 10px 15px;
    font-weight: 700;
    font-size: 25px;
}

.text {
    text-align: center;
}